Why isn't Captain Atom in the JLA? Slight spoilers for JLA 5

Towards the end of JLA #5 when Waller is talking about remaking the team she mentions him and it occurred to me that he is the perfect fit due to his military background.

He also makes a much better counter for Wonder woman than Kantana.

The only reason i can see that he's not on the team is that would make the JLA more powerful than the JL (Which is what Waller wanted, but probably not the editors)

Are there any other reasons why he wasn't approached?

Is he even in the 21st century any more? Last I checked he was in the LOSHverse without his memory as Captain Adym.

I would love to see him in either team.I always liked him as part of the Justice League.

Too powerful.

Pre-New 52 Atom would've been better suited to JLA but the New 52 Atom is basically Dr. Manhattan, I don't think anybody except the Flash can take him down.

Captain Atom could solo the JL

But the fact that he is extremely powerful and has military experience is exactly what Waller wanted in the JLA.